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Leonard Zon, professor of Stem Cell and Regenerative Biology and director of the Stem Cell Research Program at Boston Children’s Hospital, has won 2026 March of Dimes Richard B Johnston Jr., MD Prize from the March of Dimes for his pioneering work in hematology and stem cell biology.
Zon, who is also the Grousbeck Professor of Pediatric Medicine at Harvard Medical School, was one of the first scientists to use zebrafish as model organisms for revealing new insights about human diseases, especially blood disorders and cancers in children. The small tropical fish have transparent embryos and produce up to 300 offspring per week
In the 1990s, the Zon team discovered five genes involved in human blood diseases. One of the most significant was the gene that produces the iron transporting protein known as ferroportin. The gene helps ensure that iron — a critical element used by oxygen-carrying hemoglobin — is delivered from mother to baby through the placenta. The discovery yielded new insights for understanding iron deficiency and anemia.
In 2007, the Zon lab showed how the hormone prostaglandin E2 could dramatically boost stem cell populations in zebrafish. Later clinical trials showed that adding it to umbilical cord blood in humans also greatly increased the stem cell populations.
These discoveries improved transplant procedures for leukemia patients and these treatments now are routinely used for genetic blood diseases such as sickle cell anemia, thalassemia, and primary immunodeficiencies.
Zon’s research has led to the development of a therapeutic for Diamond-Blackfan anemia that is nearing clinical trials; another treatment for the pediatric disease spinal muscular atrophy currently is under review by the U.S. Food and Drug Administration.
“Ever since my first experience working with leukemia patients early in my research career, I’ve been trying to uncover the mysteries of blood to help those affected by blood and other diseases,” said Zon, who also works as a clinical physician in addition to his stem cell research. “So, to be instrumental in the discovery of new pathways that underscore blood development in embryos and to have a real impact on diseases affecting kids and babies, that’s priceless.”
